This training program is designed to prepare young scientists for independent careers in immunological research. The need for bright, thoroughly trained investigators in this area is great: diseases of autoimmunity, congenital and acquired immunodeficiency, and lymphoid neoplasms are among the most significant and perplexing causes of morbidity today. Research at the level of cellular and molecular mechanisms of host defense is also critical for elucidating and preventing the immunologic complications of bone marrow and solid organ transplantation and immune responses to gene therapy. Trainees (predoctoral and postdoctoral (M.D. or Ph.D.) fellows) are mentored by one of 17 program faculty with primary or joint appointments in the Department of Immunology at Baylor College of Medicine, whose research programs address diverse areas of modern immunology, including lymphocyte activation and apoptosis, lymphocyte differentiation, immune responses, inflammation, HIV, gene therapy, hematopoeitic stem cell biology, adhesion molecules, and cyotokines. Trainees: Support for three predoctoral and three postdoctoral trainees is requested. Predoctoral trainees are selected primarily from among students who have matriculated into the Immunology graduate program and chosen one of the training faculty as their thesis mentor. Students who have entered the laboratories of participating faculty through other programs may also be considered. These trainees complete a core curriculum in basic and advanced areas of immunology and in modern cell and molecular biology. Postdoctoral trainees are selected from highly qualified Ph.D. or M.D. applicants to individual training faculty or sought through advertisements. In addition to faculty guidance of research training and career development, postdoctoral trainees may take advanced immunology courses. Training Facilities and Environment: There are 35 faculty in the Department of Immunology. Nine of the ten primary faculty are housed in approximately 23,000 square feet of contiguous space, including 12,300 square feet in the Alkek Center for Graduate Research. Collectively, the training faculty bring in over $17.0 million in annual direct grant costs and occupy approximately 41,000 square feet of laboratory space, including the Department of Immunology and modern research facilities in the central Baylor complex and the Houston VA, Texas Children's, and Methodist hospitals. Currently there are 29 predoctoral students in the Department and 45 postdoctoral fellows in the program faculty's laboratories. Training occurs in the research environment of Baylor College of Medicine, highly ranked among medical schools worldwide and a leader in NIH funding. The Texas Medical Center is the largest medical center in the world, and provides a highly interactive training environment rich in collaborations.